WO2018105208A1

WO2018105208A1 - Wireless terminal and wireless base station allocation method

Info

Publication number: WO2018105208A1
Application number: PCT/JP2017/035600
Authority: WO
Inventors: 加藤　修; 紀之志水; 正哲吉野; 青山　恭弘
Original assignee: パナソニック株式会社
Priority date: 2016-12-06
Filing date: 2017-09-29
Publication date: 2018-06-14
Also published as: US20190297628A1; US10986635B2; JP2018093428A; JP6574159B2

Abstract

A wireless terminal capable of communicating with multiple wireless base stations through a network in which multiple wireless communication methods are used in a mixed manner. A storage unit stores, as a communication history, at least location information for the wireless terminal and information pertaining to the wireless base station at the time of communication with each wireless base station. An acquisition unit acquires the location information for the wireless terminal. On the basis of the acquired location information for the wireless terminal and the communication history stored in the storage unit a derivation unit derives a connection base station from the multiple wireless base stations, as the wireless base station to be used in data communication. A communication unit performs data communication with the derived connection base station.

Description

Wireless terminal and wireless base station allocation method

The present disclosure relates to a radio terminal and a radio base station assignment method that determine and assign a radio base station that is a communication partner during radio communication.

2. Description of the Related Art Conventionally, there is a technique for estimating a moving means (for example, a bus or a railway route) used by a user who has a portable mobile terminal based on a communication history of a portable mobile terminal capable of communication represented by a smartphone or a tablet terminal type computer. Exists. For example, in Patent Document 1, the route estimation device determines a route used by a user who owns a mobile terminal based on a representative value (for example, an average value) of a distance between a position where the mobile terminal communicates and a position of, for example, a railway line. presume.

Japanese Unexamined Patent Publication No. 2016-147331

The present disclosure has been devised in view of the above-described conventional circumstances, and based on the communication history at its current position, determines and assigns a wireless base station to be a communication partner at the time of a wireless communication connection request, to the optimum cell. A wireless terminal and a wireless base station assignment method that suppress deterioration of the connection probability of the wireless communication device are provided.

The present disclosure is a wireless terminal capable of communicating with a plurality of wireless base stations via a network in which a plurality of wireless communication schemes are used together, and the past between each of the wireless base stations At the time of communication, at least the location information of the wireless terminal and information related to the wireless base station are accumulated as a communication history, an acquisition unit that acquires the location information of the wireless terminal, and the acquired wireless terminal A deriving unit for deriving a connection base station as a radio base station used for data communication from the plurality of radio base stations based on the location information and the communication history accumulated in the accumulation unit, and the derived connection And a communication unit that performs the data communication with a base station.

Further, the present disclosure is a radio base station allocation method in a radio terminal capable of communicating with a plurality of radio base stations via a network in which a plurality of radio communication schemes are used in combination. A step of accumulating at least the location information of the radio terminal and information about the radio base station in a storage unit as a communication history during past communication with the radio base station; and a step of acquiring the location information of the radio terminal Based on the acquired location information of the wireless terminal and the communication history stored in the storage unit, a connection base station as a wireless base station used for data communication is derived from the plurality of wireless base stations. There is provided a radio base station allocation method comprising the steps of: performing the data communication with the derived connection base station.

According to the present disclosure, since it is possible to determine and assign a wireless base station to be a communication partner at the time of a wireless communication connection request based on a communication history at its current position, it is possible to suppress deterioration in the optimal connection probability to the cell. .

It is a schematic diagram which shows an example of the heterogeneous network comprised with the radio | wireless communications system of this Embodiment. It is a block diagram which shows an example of an internal structure of the radio | wireless terminal of this Embodiment in detail. It is a schematic diagram which shows an example of the accumulation communication history table T1 which hold | maintained the communication history for every position of a radio | wireless terminal. It is a schematic diagram which shows an example of the high-order communication log | history table T2 which shows the correspondence of upper n distance Di and radio | wireless resource (radio base station-radio frequency). It is a flowchart explaining in detail an example of the operation | movement procedure when the communication connection request | requirement generate | occur | produces in the radio | wireless terminal of this Embodiment. It is a flowchart explaining in detail an example of the operation | movement procedure when the communication connection request | requirement generate | occur | produces in the radio | wireless terminal of this Embodiment.

In recent years, in a wireless communication system in which a wireless terminal and a wireless base station apparatus are connected to a network, a heterogeneous network in which a small cell having a relatively small cell radius and a macro cell having a relatively large cell radius are superposed has been studied. Has been made. In this heterogeneous network, it is assumed that the throughput (bps) of the small cell is orders of magnitude greater than the throughput (bps) of the macro cell.

For example, the macro cell is LTE (Long Term Evolution), and the cell throughput is 300 Mbps. If the number of wireless terminals connected to the macro cell is 100, the throughput per terminal is 3 Mbps. On the other hand, the small cell is 5G (5th generation mobile communication system), and the cell throughput is 10 Gbps. Even if the number of wireless terminals connected to the small cell is 100, the throughput per terminal is 100 Mbps, if the number of wireless terminals connected to the small cell is 10, the throughput per terminal is 1 Gbps, and if the number of wireless terminals connected to the small cell is 2, 1 The throughput per terminal is 5 Gbps, which is an order of magnitude larger than that of a macro cell. Therefore, in a heterogeneous network, it is desired to connect a moving wireless terminal to a small cell as much as possible.

Here, when a wireless terminal performs wireless communication, a wireless base station that is a communication partner with which the wireless terminal is wirelessly connected and, if necessary, a wireless frequency (in other words, a carrier frequency or a wireless channel) that the wireless terminal uses for wireless communication. Decide and assign. However, in Patent Document 1 described above, it is not considered to determine a radio base station and a radio frequency that are required when the radio terminal performs radio communication using the communication history of the mobile mobile terminal. It is difficult to make a decision.

In the heterogeneous network described above, the ratio of the small cell area to the entire area is small, and the probability that a moving wireless terminal misses an opportunity to connect to the optimal cell (in other words, a small cell with high throughput) at each position is low. As the time required for cell selection increases, the time increases. Therefore, there is a method in which the entire coverage area of the heterogeneous network is divided into area blocks of a certain size, the position of the wireless terminal is associated with the area block number, and the connection to the optimum cell is attempted using the communication history for each area block number. Proposed. For example, based on the current location information and communication history stored for each area block number, the radio terminal searches for a radio base station that has connected in the past and executed radio communication in that location and area block.

However, in this method, if the area block is large (for example, 1 km × 1 km), a large communication history can be accumulated for each area block. However, the base station most suitable for connection at the current pinpoint position of the wireless terminal (in other words, The probability of misrecognizing (cell) increases. On the other hand, if the area block is small (for example, 5 m × 5 m), the number of area blocks becomes enormous, and the accumulation of communication history is excessively divided, so that the communication history for each area block becomes too small. It becomes difficult to select a base station (in other words, a cell) most suitable for connection at the pinpoint position. Therefore, the requirements for the position accuracy (positioning accuracy) and the time required for specifying the position of the wireless terminal are also increased. Furthermore, in the above-described method, the amount of prior work for dividing the entire coverage area of the heterogeneous network into area blocks is large regardless of the size of the area blocks.

Hereinafter, the present embodiment that specifically discloses the radio terminal and radio base station allocation method according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art. The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

FIG. 1 is a schematic diagram showing an example of a heterogeneous network 20 configured by the wireless communication system 10 of the present embodiment. The radio communication system 10 is configured to include at least one radio terminal 100 and a plurality of radio base stations 200. The radio terminal 100 and each radio base station 200 are connected via a radio communication line. In FIG. 1, for simplicity of explanation, only one wireless terminal 100 is shown, and the X axis in the horizontal direction of FIG. 1 and the Y axis in the vertical direction of the paper, the Y axis, and the X axis and the Y axis are both perpendicular. The Z-axis direction is defined in such a direction.

The wireless communication system 10 constitutes a heterogeneous network 20 in which each wireless base station 200, which is a communication partner to which the wireless terminal 100 is connected during wireless communication, can execute wireless communication based on different wireless standard systems. The radio terminal 100 communicates with the radio base station 200. That is, in the heterogeneous network 20, a plurality of radio base stations 200 corresponding to a plurality of different radio communication schemes (for example, radio access technology (RAT: Radio Access Technology) or cell radius) are mixed. In the heterogeneous network 20, for example, wireless base stations 200 having different cell radii overlap in a plane, including a mixture of a plurality of types of wireless standards. The RAT includes, for example, information on a wireless communication standard and a radio frequency.

The heterogeneous network 20 may not be a C / U separation type network or a C / U separation type network. In this embodiment, a network that is not a C / U separation type is illustrated. That is, in the radio communication system 10, the communication related to the control data and the communication related to the user data are performed by the same radio base station 200.

The radio base station 200 includes a macro cell radio base station 200A and a small cell radio base station 200B. The radio terminal 100 communicates control data and user data with both the macro cell radio base station 200A and the small cell radio base station 200B. The control data includes data related to C (Control) -Plane. The user data includes data related to U (User) -Plane. The user data includes, for example, image data (for example, moving images and still images) and audio data, and may include data with a large data amount.

C-plane is a communication protocol for communicating control data for call connection and radio resource allocation in radio communication. U-plane is a communication protocol for actual communication (for example, video communication, voice communication, data communication) between the wireless terminal 100 and the wireless base station 200 using the allocated wireless resources.

The cell radius of the macrocell radio base station 200A is, for example, 1 km to several km and is relatively large. The RAT that can be adopted by the macrocell radio base station 200A is, for example, one type (for example, LTE). The cell radius corresponds to the maximum transmission distance of the radio base station 200.

The cell radius of the small cell radio base station 200B is, for example, 10 m to 100 m and is relatively small. There are various types of RATs that can be adopted by the small cell base station 200B, and there are a plurality of types. For example, the cell radius may be 100 m or more in a mountainous area, a desert area, or a forest area, or may be larger than the cell radius of the macrocell radio base station 200A. That is, here, the distinction between the macro cell radio base station 200A and the small cell radio base station 200B is not conscious of the size of the cell radius.

In FIG. 1, “MBS” (▲) indicates the macro cell radio base station 200A, “SBS” (Δ) indicates the small cell radio base station 200B, and “T” indicates the radio terminal 100. A line surrounding the macro cell radio base station 200A indicates a communicable range by the macro cell radio base station 200A. A line surrounding the small cell radio base station 200B indicates a communicable range by the small cell radio base station 200B. The communicable range of the radio base station 200 is determined according to the position of the radio base station 200 and the cell radius, for example.

The radio terminal 100 and the radio base station 200 set RATs used for radio communication from RATs (for example, radio communication standards and radio frequencies) that can be adopted, and perform radio communication using the set RATs. Each wireless terminal 100 and wireless base station 200 can employ one or more RATs.

Wireless communication standards include, for example, LTE (Long Term Evolution), wireless LAN (Local Area Network), DECT (Digital Enhanced Cordless Telecommunication), 3G (third generation mobile communication system), 4G (fourth generation mobile communication system), 5G. (5th generation mobile communication system).

Specific information on RAT includes, for example, the following RAT1 to RAT5. RAT1 is, for example, LTE having a radio frequency band of 700 MHz to 3 GHz. RAT2 is, for example, LTE-Advanced with a radio frequency band of 15 GHz. RAT3 is, for example, wireless LAN communication with a radio frequency band of 5 GHz. RAT4 is, for example, a radio communication system with a radio frequency band of 15 GHz, and is a fifth generation mobile communication system. RAT5 is, for example, a radio communication system (for example, millimeter wave communication) (for example, WiGig) having a radio frequency band of 60 GHz.

FIG. 2 is a block diagram showing in detail an example of the internal configuration of the wireless terminal 100 of the present embodiment. The wireless terminal 100 includes a processor 150, a memory 160, a GPS (Global Positioning System) antenna 101, a GPS receiving unit 102, a transmitting antenna 108, a receiving antenna 109, a BLE (Bluetooth (registered trademark) Low Low Energy) antenna 121, and a BLE receiving unit 122. It is the structure containing.

The processor 150 performs various processes and controls in cooperation with the memory 160. Specifically, the processor 150 refers to a program and data held in the memory 160 and executes the program, thereby realizing the functions of the following units. Each unit includes a position information generation unit 103, a base station derivation unit 104, a radio resource allocation management unit 105, a transmission packet generation unit 106, a radio transmission unit 107, a radio reception unit 110, and a reception packet decoding unit 111.

The memory 160 includes, for example, a RAM (Random Access Memory) as a work memory used during processing of the wireless terminal 100, and a ROM (Read Only Memory) that stores programs and data that define the operation of the wireless terminal 100. Various data and information are temporarily stored in the RAM. In the ROM, a program that defines the operation of the radio terminal 100 (for example, processing (step) to be performed as the radio base station allocation method according to the present embodiment) is written.

Also, the memory 160 as an example of the storage unit stores a cumulative communication history table T1 and a higher communication history table T2 described later. In FIG. 1, the memory 160 is shown as a separate configuration from the processor 150, but may be built in the processor 150. The memory 160 may include a secondary storage device together with the primary storage device.

The GPS antenna 101 receives a plurality of signals indicating times and positions (coordinates) of the GPS satellites 50 transmitted from a plurality of (for example, three or four) GPS satellites 50 and outputs the signals to the GPS receiver 102. Each GPS satellite 50 transmits a signal indicating the time and the position (coordinates) of each GPS satellite 50.

The GPS reception unit 102 as an example of the acquisition unit is based on a plurality of signals received by the GPS antenna 101, and the position information of the GPS reception unit 102 (that is, the position information of the wireless terminal 100 itself (own position information)). Is calculated and obtained. The position information obtained by this calculation indicates the current position of the wireless terminal 100 located outdoors, for example. Note that the GPS receiving unit 102 may be provided in the processor 150. The GPS receiver 102 outputs the position information of the wireless terminal 100 obtained by the calculation to the processor 150. The calculation of the position information of the GPS receiving unit 102 may be performed by the position information generating unit 103 of the processor 150 instead of the GPS receiving unit 102. In this case, the position information generating unit 103 is input with information indicating the time and the position of each GPS satellite 50 included in the plurality of signals received by the GPS antenna 101 via the GPS receiving unit 102.

Here, when the wireless terminal 100 is located outdoors, the reliability of the position information of the wireless terminal 100 calculated based on the signals from the plurality of GPS satellites 50 described above is considerably high. However, when the wireless terminal 100 is located indoors (for example, in a building or underground mall, but not limited to the same; the same applies hereinafter) or near the boundary between the outdoors and indoors, The position information of the wireless terminal 100 calculated based on the signal may include a certain error. As described above, when the wireless terminal 100 is located indoors or near the boundary between the outdoor and the indoor, the wireless terminal 100 transmits the time transmitted from the plurality of BLE beacons 60 installed indoors and each BLE beacon 60. Based on a plurality of signals indicating the position (coordinates) of the wireless terminal 100, the current position information of the wireless terminal 100 itself (the position information of itself) is calculated and acquired. For example, if the wireless terminal 100 determines that the received electric field strength (RSSI: Received Signal Strength Strength Indicator) of the signal from the BLE beacon 60 is larger than a predetermined threshold, the wireless terminal 100 is located indoors or near the boundary between the outdoor and indoor. Based on the signal transmitted from the plurality of BLE beacons 60, its own position information is calculated. Note that the method for determining that the wireless terminal 100 is located indoors or near the boundary between the outdoor and indoor is not limited to the method based on the comparison result between the received electric field strength and a predetermined threshold value.

The BLE antenna 121 receives a plurality of signals indicating the time transmitted from a plurality of (for example, two) BLE beacons 60 and the position (coordinates) of each BLE beacon 60 and outputs the signals to the BLE receiving unit 122. Each BLE beacon 60 transmits a signal indicating the time and the position (coordinates) of each BLE beacon 60. Moreover, the distance between each BLE beacon 60 is known. Each wireless terminal 100 may acquire distance information between the respective BLE beacons 60 in advance, or may be directly or via an external device (not illustrated. For example, another wireless terminal, distance information) via a network (not illustrated). You may acquire from a management server.

The BLE receiving unit 122 as an example of the acquiring unit uses the triangulation method, for example, based on a plurality of signals received by the BLE antenna 121, that is, position information of the BLE receiving unit 122 (that is, position information of the wireless terminal 100 itself). (Own position information)) is calculated and acquired. The position information obtained by this calculation indicates the current position of the wireless terminal 100 located indoors or near the boundary between the outdoors and the indoors.

Note that the BLE receiving unit 122 uses a combination of a plurality of signals received by the BLE antenna 121 and a known method (for example, PDR (Pedestrian DeadeckReckoning) or PMM (Pedestrian Map Matching)), or inside the wireless terminal 100 or Position information in the vicinity of the boundary between the outdoor and indoor may be calculated.

Here, since it can be said that the installation positions of the respective BLE beacons 60 have information on latitude, longitude, and altitude, the wireless terminal 100 is indoors, or outdoors and indoors, as in the case where the wireless terminal 100 is located outdoors. Even when located near the boundary, the outdoor location information acquisition method can be expanded indoors, and location information similar to latitude, longitude, and altitude can be acquired. The BLE receiving unit 122 may be provided in the processor 150. The BLE receiving unit 122 outputs the position information of the wireless terminal 100 obtained by the calculation to the processor 150. Note that the calculation of the position information of the BLE receiving unit 122 may be performed by the position information generating unit 103 of the processor 150 instead of the BLE receiving unit 122. In this case, the position information generating unit 103 is input with information indicating the time included in the plurality of signals received by the BLE antenna 121 and the position of each BLE beacon 60 via the BLE receiving unit 122.

FIG. 3 is a schematic diagram illustrating an example of a cumulative communication history table T1 that holds a communication history for each position of the wireless terminal 100. The accumulated communication history table T1 is the accumulated communication when the wireless terminal 100 has performed wireless communication with any one of the plurality of wireless base stations 200 (hereinafter also referred to as “connected base station”) in the past. Holds history (communication performance) information. The connection base station is the radio base station 200 that is connected to the radio terminal 100 for communication. The accumulated communication history table T1 is held in the memory 160 of each wireless terminal 100.

The communication history stored in the cumulative communication history table T1 includes, for example, information indicating the order (order i) when the wireless terminal 100 performs wireless communication with the connected base station, and the position of the wireless terminal 100 during the wireless communication (order i). Information indicating latitude X, longitude Y, altitude Z), information indicating the identification number m of the connecting base station, and information indicating the radio frequency n (carrier frequency). For example, at the time of communication connection with the first connected base station, the wireless terminal 100 exists at the position (X1, Y1, Z1), and the number 1 is connected to the number 3 connected base station. It means that radio communication is performed using a radio frequency (carrier frequency). The numbers of the connecting base station (radio base station) and the radio frequency (carrier frequency) are known in each radio terminal 100 using the heterogeneous network 20 shown in FIG. . In FIG. 3, for example, a communication history for 100 times is shown as the past cumulative total. For example, a communication history for 300 times may be used as the past total.

Although not shown in FIG. 3, the communication history includes RAT (for example, LTE) adopted by the connecting base station, the number of times of communication with the connecting base station (number of times of wireless connection), and communication related to the communication with the connecting base station. Information on the amount (communication data amount) may be included.

In this embodiment, the communication history between the wireless terminal 100 and the connected base station is managed in the memory 160 as the cumulative communication history table T1. Further, when a communication connection with a connection base station derived by a base station deriving unit 104 described later is tried and succeeded, the communication history is updated by a radio resource allocation management unit 105 as an example of an updating unit (for example, (See step S12 in FIG. 6 described later).

For example, when the wireless terminal 100 is located outdoors, the position information generation unit 103 determines the position information of the wireless terminal 100 (that is, the current position information of the wireless terminal 100) based on the information from the GPS receiving unit 102. It is generated and output to the base station derivation unit 104. For example, when the wireless terminal 100 is located indoors or near the boundary between the outdoors and the indoors, the position information generation unit 103 uses the information from the BLE receiving unit 122 to determine the position information of the wireless terminal 100 (that is, the current information (Position information of the wireless terminal 100) is generated and output to the base station deriving unit 104.

The base station deriving unit 104 as an example of a deriving unit includes the position information of the wireless terminal 100 generated by the position information generating unit 103 (that is, the current position information of the wireless terminal 100) and the accumulated communication history table T1 in the memory 160. Based on the above, candidate connection base stations and radio frequencies used for data (for example, control data, user data) communication are derived from the plurality of radio base stations 200 in the heterogeneous network 20. The base station deriving unit 104 allocates a radio resource (for example, (1) an identification number of the radio base station or (2) an identification number of the radio base station and an identification number of the radio frequency (carrier frequency)) The data is output to the management unit 105.

Specifically, the base station deriving unit 104 includes a predetermined number (k: default value) of communication history with a small distance Di based on the current location information of the wireless terminal 100 and the location information of the wireless terminal 100 in the communication history. Thus, the connection base station and the radio frequency are derived preferentially from the radio base station (connection base station) and the radio frequency that are frequently assigned to the radio communication.

FIG. 4 is a schematic diagram showing an example of the upper communication history table T2 indicating the correspondence between the top n distances Di and the radio resources (radio base station-radio frequency). The upper communication history table T2 is generated by the base station deriving unit 104. The upper communication history table T2 is the position information of the wireless terminal 100 when wireless communication is performed between the current position information of the wireless terminal 100 and the past connected base station in the communication history of the cumulative communication history table T1. The upper predetermined number (k) of communication histories having a small distance Di between and are extracted. The upper communication history table T2 is held in the memory 160 of each wireless terminal 100.

The communication history held in the upper communication history table T2 includes, for example, information indicating the order (order i) when the wireless terminal 100 performs wireless communication with the connected base station, and the position of the wireless terminal 100 at the time of wireless communication (order i). Information indicating the distance Di between the position (latitude X, longitude Y, altitude Z) of the current wireless terminal 100, information indicating the identification number m of the connected base station, and radio It has associated with information indicating the frequency n (carrier frequency). FIG. 4 shows an example where the predetermined number (k) is 10. That is, the distance Di “0.07” is the minimum value (that is, the position closest to the current position of the wireless terminal 100 and has a past communication record), and the distance Di “0.89” is the maximum value (that is, Among the top 10 communication histories, it is the position farthest away from the current position of the wireless terminal 100 and the past communication performance). For example, when the distance Di is the smallest “0.07”, this means that the wireless terminal 100 has performed wireless communication with the connected base station of number 3 using the wireless frequency (carrier frequency) of number 2. To do. Similarly, when the distance Di is the largest “0.89”, the wireless terminal 100 has performed wireless communication with the connected base station of the number 3 using the wireless frequency (carrier frequency) of the number 2. means.

The cumulative communication history table T1 and the upper communication history table T2 may be provided separately for the uplink 21 and for the downlink 22, or may be provided in common. The RAT that can be adopted by the radio base station 200 held in the cumulative communication history table T1 and the upper communication history table T2 is a RAT that can also be adopted by the radio terminal 100.

Note that the uplink 21 is a radio channel from the radio terminal 100 to the radio base station 200. The downlink 22 is a radio link that goes from the radio base station 200 to the radio terminal 100. Wireless lines widely include various public lines, mobile phone lines, wide area wireless lines, and the like.

Here, an example in which the base station deriving unit 104 derives (calculates) a connected base station and a radio frequency will be specifically described with reference to FIGS. As shown in FIG. 3, it is assumed that the communication history for 100 times is held in the cumulative communication history table T1 in the past, and the 101st communication connection request is generated in the wireless terminal 100 at the position (Xk, Yk, Zk).

The base station deriving unit 104 refers to the accumulated communication history table T1 in FIG. 3 and determines the current position (Xk, Yk, Zk) of the wireless terminal 100 and the position (Xi, Yi, Zi) of the wireless terminal 100 in the communication history. A distance Di based on the above is calculated according to Equation (1). Here, i = 1 to 100. Note that the calculation example of the distance Di is not limited to the Hamming distance of Expression (1), and may be the Euclidean distance of Expression (2).

The base station deriving unit 104 uses the top 10 (for example, n = 10) order i among the distances Di calculated by Formula (1) or Formula (2), and the identification number m of the connected base station. 4 and information indicating the radio frequency n (carrier frequency) are extracted to generate the upper communication history table T2 of FIG. As shown in the upper communication history table T2 of FIG. 4, the wireless resource (eg, the identification number of the connecting base station−the identification number of the wireless frequency) is 4 times for the wireless resource (3-2) and 3 times for the wireless resource (2-1). Thus, it can be determined that the wireless resource (9-2) has been used (allocated) once, the wireless resource (7-3) once, and the wireless resource (4-2) once.

Therefore, the base station deriving unit 104 sets the priority of the radio resource to be allocated in response to the 101st new communication connection request as the radio resource (3-2) → the radio resource (2-1) → the radio resource (9 -2) → Radio resource (7-3) → Radio resource (4-2) is determined (derived). The priority order of radio resource candidates to be allocated is determined in this way, but it is also assumed that the radio resource (3-2) is not necessarily the best radio resource candidate for the current radio terminal 100. This is because the wireless resource (3-2) may be occupied by other wireless terminals existing in the heterogeneous network 20. What is important is that the base station deriving unit 104 narrows down the priority of radio resources to be allocated.

Here, the order of the radio resource (9-2), the radio resource (7-3), and the radio resource (4-2) corresponds to the order from the smallest distance Di. As a result, the base station deriving unit 104 can assign the connection base station and the radio frequency in descending order of the past wireless communication performance of the wireless terminal 100, and in a more stable communication environment at the current position of the wireless terminal 100. Comfortable data communication can be facilitated.

Here, it has been described that the base station deriving unit 104 extracts both information indicating the identification number m of the connected base station and information indicating the radio frequency n (carrier frequency) as radio resource candidates. Only information indicating the station identification number m may be extracted, and so on. That is, in the following description, radio resources include (1) both information indicating the identification number m of the connecting base station and information indicating the radio frequency n (carrier frequency), and (2) the identification number m of the connecting base station. 2 patterns of only information indicating

Note that the base station derivation unit 104 calculates the distance Di having a three-dimensional element as in the formulas (1) and (2), but considers the Z coordinate in the formulas (1) and (2). You may calculate the distance Di which has a two-dimensional element which cannot enter. As a result, when only the two-dimensional element needs to be considered as the distance Di (for example, when a new communication connection is requested at the same altitude position as in all past wireless communication), the upper communication history table T2 is generated. The calculation load of the base station deriving unit 104 when doing so is reduced.

The base station deriving unit 104 generates the upper communication history table T2 using all the communication histories of the cumulative communication history table T1 in the above-described calculation of the distance Di. For example, the upper communication history table T2 may be generated using only the communication history of 10 or 30). Thereby, the calculation load of the base station deriving unit 104 when generating the upper communication history table T2 is reduced.

In addition, the base station deriving unit 104 uses the predetermined number of communication histories from the communication history in the same time zone as the time when a new communication connection request is made to the wireless terminal 100 to obtain the upper communication history table T2. It may be generated. As a result, the base station deriving unit 104 can generate a higher communication history table T2 having a communication history corresponding to a different communication environment for each time zone, such as a daytime time zone or a night time zone.

Further, the base station deriving unit 104 generates a higher-level communication history table T2 by extracting a predetermined number (k) of communication histories from only communication histories whose distance Di is equal to or less than a predetermined threshold value Dth (default value). May be. This eliminates the communication history in which the distance Di is greater than the predetermined threshold value Dth (in other words, the communication history when the position of the wireless terminal 100 in the past wireless communication is far away from the current position) and performs higher-level communication. Since the history table T2 can be generated, the wireless terminal 100 can perform more appropriate wireless resource allocation along the network environment provided around the current position.

Note that the base station deriving unit 104 gives priority to the connection base station and the radio frequency with the highest number of allocations of radio resources (connection base station identification number-radio frequency identification number) in the higher communication history table T2. Although it has been described that the station and the radio frequency are derived, the deriving method is not limited to this. For example, the base station deriving unit 104, when the communication data amount is included in the communication history of the higher communication history table T2, the connected base station and the radio frequency having a large communication data amount (in other words, the number of transmitted / received data bytes) The connection base station and the radio frequency may be derived with priority given to. As a result, the wireless terminal 100 adds a small cell (in other words, a cell that is likely to have a large amount of communication data) that can obtain a high-speed throughput such as 5G (fifth generation mobile communication system) to the heterogeneous network 20, for example. It becomes possible to preferentially assign a connectable base station and a radio frequency that can be provided, and it becomes easy to perform a comfortable amount of communication data.

Note that the base station deriving unit 104 may multiply a specific factor (for example, altitude) out of the position (latitude, longitude, altitude) of the wireless terminal 100 by a weighting coefficient when calculating the distance Di (see Equation (3)). ). In Equation (3), the coefficient of | Zk−Zi | is only an example of a weighting coefficient. Even if the latitude and longitude are the same in the position information of the wireless terminal 100, the communication environment may differ greatly if the altitude is different. In such a case, the base station deriving unit 104 can provide a communication environment suitable for the current position of the radio terminal 100 by considering (specifically, multiplying) the above-described weighting coefficient (for example, 10). And a base station and a radio frequency can be derived.

The radio resource allocation management unit 105 acquires the radio resource derivation result output from the base station deriving unit 104. The radio resource derivation result includes, for example, a connection base station as a radio resource derived by the base station deriving unit 104 and the priority order of the radio frequency, for example, between the candidate connection base station and the radio terminal 100. Information on what the wireless communication standard is, and information on the frequency band may be included.

The radio resource allocation management unit 105 allocates and manages radio resources used for radio communication with the connection base station in cooperation with the connection base station. This radio resource includes, for example, a radio frequency used for radio communication and a radio frequency resource block (RB). The resource block refers to a unit of radio frequency allocation divided by, for example, a radio frequency (eg, subcarrier frequency) frequency axis and a time axis (eg, time slot).

The radio resource allocation management unit 105 inquires of the connecting base station whether or not the radio frequency allocation candidate resource block can be allocated. Based on the radio frequency allocation candidates, the connecting base station searches the resource block allocation status of this radio frequency, determines whether the resource block can be allocated, and transmits the determination result to the radio terminal 100. The radio resource allocation management unit 105 refers to the determination result and determines whether or not a resource block of an allocation candidate radio frequency can be allocated. The determination result includes, for example, information on whether or not resource blocks can be allocated, and information on radio frequency resource blocks allocated when resource blocks can be allocated.

The radio resource allocation management unit 105 allocates an unallocated resource block of a radio frequency used for communication with the connected base station based on the determination result. Further, the radio resource allocation management unit 105 may specify AMC (Adaptive Modulation and Coding) while allocating resource blocks.

If the allocation candidate radio frequency cannot be allocated, the radio resource allocation management unit 105 changes the radio frequency to the one with the next priority, and newly starts the radio frequency from the allocation candidate with the next priority. Select the frequency. When there is no radio frequency to which a resource block can be allocated to the connected base station, the radio resource allocation management unit 105 changes the connected base station to the one having the next priority, and the allocation candidate of the next priority is selected. A new connection base station is selected from the connection base stations.

Also, the radio resource allocation management unit 105 acquires radio resource usage history information from the transmission packet generation unit 106 or the reception packet decoding unit 11. The usage history information includes, for example, information on a connection base station that wirelessly communicates with the wireless terminal 100, information on a radio frequency used for communication with the connection base station, and a communication amount communicated using the radio frequency. Information. The radio resource allocation management unit 105 as an example of the update unit performs communication included in the usage history information with respect to the radio frequency of the cumulative communication history table T1 that matches the radio frequency included in the acquired usage history information, for example. The cumulative communication history table T1 may be updated by adding the amount.

The radio resource allocation management unit 105 sends the allocated radio resource information, that is, the radio frequency and resource block information used for communication with the connected base station, to the radio transmission unit 107 or the radio reception unit 110. In this case, the radio resource allocation management unit 105 sends the allocated radio resource information for the uplink 21 to the radio transmission unit 107. Also, the radio resource allocation management unit 105 sends the allocated radio resource information for the downlink 22 to the radio reception unit 110.

The transmission packet generation unit 106 generates a packet (transmission packet) to be transmitted to the radio base station 200 using the input uplink data (UL data). The transmission packet includes data of the uplink 21. Data on the uplink 21 (for example, control data and user data) is obtained from, for example, an external device (not shown) such as the memory 160 and a storage device, and various software processing units (not shown).

The transmission packet generation unit 106 sends information on the usage history of radio resources related to communication of transmission packets to the radio resource allocation management unit 105.

A radio transmission unit 107 as an example of a communication unit uses the radio resource allocated by the radio resource allocation management unit 105 to transmit the transmission packet generated by the transmission packet generation unit 106 via the transmission antenna 108 and the uplink 21. To the connected base station instructed by the radio resource allocation management unit 105.

The radio reception unit 110 as an example of a communication unit uses a radio resource allocated by the radio resource allocation management unit 105 to transmit a packet (reception packet) from the connected base station via the downlink 22 and the reception antenna 109. Receive.

Received packet decoder 111 decodes the received packet received by wireless receiver 110 to obtain decoded data. The decoded data includes data on the downlink 22. Data on the downlink 22 (for example, control data and user data) is passed to, for example, a memory 160, an external device (not shown) such as a storage device or a display device, and processing units (not shown) of various software.

Further, the data of the downlink 22 may include information on connection candidate base stations selected by a known method. Information on this connection candidate base station is sent to the radio resource allocation management unit 105.

Further, the data on the downlink 22 may include control information related to radio resource allocation. This control information is sent to the radio resource allocation management unit 105. This control information includes, for example, a determination result in which it is determined whether or not a resource block can be allocated by the connecting base station.

Also, the received packet decoding unit 111 sends information on the usage history of radio resources related to communication of received packets to the radio resource allocation management unit 105.

Next, an operation procedure when a new communication connection request is generated in the wireless terminal 100 of the wireless communication system 10 of the present embodiment will be described with reference to FIG. 5 and FIG.

5 and 6 are flowcharts illustrating in detail an example of an operation procedure when a communication connection request is generated in the wireless terminal 100 of the present embodiment. 5 and 6, for the sake of simplicity, the case where the wireless terminal 100 is located outdoors will be described as an example. However, the wireless terminal 100 is located indoors or near the boundary between the outdoors and indoors. But the same is true.

In FIG. 5, the radio reception unit 110 or the radio transmission unit 107 of the radio terminal 100 determines whether or not a new connection request has occurred (S1). This connection request includes, for example, a connection request from the wireless terminal 100 to the wireless base station 200 or a connection request from the wireless base station 200 to the wireless terminal 100. For example, when the wireless terminal 100 acquires and reproduces moving image data on a content server (not shown), a connection request from the wireless terminal 100 to the wireless base station 200 is generated. For example, when a call is received from another wireless terminal to the wireless terminal 100, a connection request from any one of the wireless base stations 200 to the wireless terminal 100 is generated.

The GPS receiving unit 102 calculates and acquires position information of the GPS receiving unit 102 (that is, position information of the wireless terminal 100 itself (own position information)) based on a plurality of signals received by the GPS antenna 101. (S2). The GPS receiver 102 outputs the position information of the wireless terminal 100 obtained by the calculation to the processor 150. For example, when the wireless terminal 100 is located outdoors, the position information generation unit 103 determines the position information of the wireless terminal 100 (that is, the current position information of the wireless terminal 100) based on the information from the GPS receiving unit 102. It is generated and output to the base station derivation unit 104.

The base station deriving unit 104 refers to the accumulated communication history table T1 in the memory 160 (S3), and the current location information of the wireless terminal 100 obtained in step S2 and the wireless terminal 100 of the communication history obtained in step S3. The distance Di based on the position information is calculated according to any one of the formulas (1) to (3) (for example, the formula (1)) (S4). Which mathematical formula is used is preset in each wireless terminal 100. The base station deriving unit 104 extracts and acquires a predetermined number (k: default value) of communication histories having a small distance Di based on the current position information of the wireless terminal 100 and the position information of the wireless terminal 100 in the communication history ( S5). The result extracted in step S5 is, for example, the upper communication history table T2 shown in FIG.

The base station deriving unit 104 determines whether or not each distance Di corresponding to all the top n communication histories extracted in step S5 is larger than a predetermined threshold Dth (S6). The predetermined threshold value Dth is, for example, 300 (meters). When the distances Di corresponding to all the top n communication histories are not larger than the predetermined threshold value Dth (S6, NO), the base station deriving unit 104 performs communication satisfying the distance Di ≦ the predetermined threshold value Dth. The radio resource (radio base station, radio frequency (carrier frequency)) included in the history is grasped (recognized) (S7).

In FIG. 6, after step S <b> 7, the base station derivation unit 104 becomes a candidate to try data (for example, control data, user data) communication among the plurality of radio base stations 200 in the heterogeneous network 20. The priority order of the connecting base station and the radio frequency is determined (S8). The radio resource allocation management unit 105 uses the radio transmission unit 107 and the radio reception unit to transmit the radio resource having the highest priority among the priorities determined in step S8 (connection base station identification number-radio frequency identification number). The communication connection to the connected base station is tried (S9). For example, the transmission packet generation unit 106 generates a transmission packet including data on the uplink 21. The wireless transmission unit 107 wirelessly transmits a transmission packet to the determined connection base station. Further, for example, the wireless reception unit 110 wirelessly receives a reception packet from the determined connection base station. Received packet decoding section 111 decodes the received packet and obtains data on downlink 22.

That is, the radio terminal 100 inquires of a candidate connection base station that tries communication connection whether or not it is possible to allocate a radio frequency resource block in radio communication with the radio terminal 100. In response to the inquiry from the wireless terminal 100, the connecting base station transmits a message indicating that the communication connection is successful to the wireless terminal 100 when determining that the resource block of the wireless frequency can be allocated.

When the communication connection is successful (S10, YES), the wireless transmission unit 107 and the wireless reception unit 110 of the wireless terminal 100 communicate data (for example, control data and user data) with the connected base station (S11). ). Further, the radio resource allocation management unit 105 as an example of the update unit includes a communication history (specifically, at least an identification number of the radio base station 200 that is a connection base station, And the identification number of the radio frequency (carrier frequency) are updated by writing them in the cumulative communication history table T1 (S12).

Note that the communication connection try in step S10 or step S19 may be either bidirectional communication or transmission or reception. Accordingly, the update of the cumulative communication history table T1 in step S12 may be performed either at the time of transmission or at the time of reception.

Here, if the communication ends (S13, YES), the processing of the wireless terminal 100 ends.

On the other hand, when the communication is not completed (S13, NO) and there is a request for a new communication connection to the wireless terminal 100 (S14, YES), the processing of the wireless terminal 100 returns to Step 2. If the communication line status with the currently connected base station (wireless base station 200) deteriorates due to movement of the wireless terminal 100 during wireless communication or the like, as shown in step S14, the wireless terminal 100 generates a new communication connection request.

If the communication is not completed (S13, NO) and there is no request for a new communication connection to the wireless terminal 100 (S14, NO), the wireless terminal 100 connects to the connected base station (communication base station that started communication in step S11). Communication with the radio base station 200) is continued (S11).

If the communication connection fails in step S10 (S10, NO), the base station deriving unit 104 excludes the communication history in which the communication connection has failed from the first extracted n communication histories (S15). After step S15, the base station deriving unit 104 determines that each distance Di corresponding to all the communication histories excluded (removed) in step S15 (for example, (n−1) communication histories) is a predetermined threshold value Dth. It is determined whether it is larger (S6). Since the processing after step S6 is the same, detailed description is omitted.

Further, when the base station deriving unit 104 determines that the distances Di corresponding to all the top n communication histories extracted in step S5 are larger than the predetermined threshold Dth (S6, NO), The method searches for a candidate for the base transceiver station 200 (cell search) in the vicinity of itself (wireless terminal 100) that can enable communication connection (S16). In this case, the base station deriving unit 104 determines a radio base station that can be a connection candidate based on a search result of the radio base station 200 located in the vicinity of the radio terminal 100.

In this known method, for example, the base station deriving unit 104 searches for the radio base stations 200 using the RATs 1 to 5 in order, and the radio transmission unit 107 notifies the search results to a predetermined base station. The predetermined base station selects a radio base station that can be a connection candidate according to the notified search result, and transmits information on the radio base station to the radio terminal 100. The base station deriving unit 104 acquires information on a radio base station that can be a connection candidate from the received packet received by the radio reception unit 110 and decoded by the reception packet decoding unit 111, and determines the information as a connection candidate radio base station.

In addition, here, as a known method, the cell search result is notified to a predetermined radio base station, and information on the radio base station that can be a connection candidate of the predetermined radio base station is transmitted to the radio terminal 100. Instead of this, the radio terminal 100 may itself determine a radio base station that can be a connection candidate based on the cell search result without notifying the cell search result to a predetermined radio base station. If there is no radio base station 200 having radio resources that can be connected in step S16 (S17, NO), there is no radio base station 200 that can be connected to the radio terminal 100. Communication becomes impossible and the process ends.

If there is a radio base station 200 having a radio resource that can be connected in step S16 (S17, YES), the base station deriving unit 104 determines this radio base station 200 as a connection candidate base station. Only one radio base station that can be a connection candidate or a plurality of radio base stations may be determined. Further, when a plurality of connection candidate base stations are determined, the base station deriving unit 104 may set priorities of the plurality of connection candidate base stations. For example, the base station deriving unit 104 sets a higher priority for connection candidate base stations having a large communication volume.

When a radio base station that can be a connection candidate is determined, the radio resource allocation management unit 105 selects this radio base station 200 as a connection base station when there is one determined radio base station. In addition, when there are a plurality of radio base stations that can be determined connection candidates, the radio resource allocation management unit 105 selects one of the radio base stations that can be a plurality of connection candidates. For example, the radio resource allocation management unit 105 may select a connection candidate base station having the largest communication volume in the past communication as a connection base station.

The radio resource allocation management unit 105 allocates radio resources used for communication with a radio base station that can be a connection candidate, and tries communication connection to the radio base station (S18). Allocation of radio resources is performed by a known method. In the known method, for example, the channel quality (interference amount) for each radio frequency is measured by the radio terminal 100 or a radio base station that can be a connection candidate, and used for communication between the radio terminal 100 and a radio base station that can be a connection candidate. Assigned radio frequency.

Regarding step S18, specifically, the radio terminal 100 determines whether or not a radio frequency resource block can be allocated in radio communication with the radio terminal 100 to a candidate connection base station to try communication connection. Inquire. In response to the inquiry from the wireless terminal 100, the connecting base station transmits a message indicating that the communication connection is successful to the wireless terminal 100 when determining that the resource block of the wireless frequency can be allocated.

When the communication connection is successful (S19, YES), the wireless transmission unit 107 and the wireless reception unit 110 of the wireless terminal 100 communicate data (for example, control data and user data) with the connected base station (S11). ). On the other hand, when the communication connection fails (S19, NO), there is no radio base station 200 that can be connected to the radio terminal 100, so that the radio terminal 100 becomes incapable of communication and the process ends.

As described above, in the radio communication system 10 according to the present embodiment, the radio terminal 100 communicates with a plurality of radio base stations 200 via the heterogeneous network 20 in which a plurality of radio communication schemes are mixedly used. Is possible. The wireless terminal 100 communicates at least the position information of the wireless terminal 100 and information about the wireless base station 200 (for example, at least the identification number of the connected base station) during the past communication with each wireless base station 200 in the communication history. And the current position information of the wireless terminal 100 is acquired. The radio terminal 100 derives a connection base station as a radio base station used for data communication from the plurality of radio base stations 200 based on the current location information of the radio terminal 100 and past communication history, and the connection base Data communication is performed with the station.

As a result, the wireless terminal 100 can determine and assign a wireless base station to be a communication partner at the time of a new wireless communication connection request based on the past communication history at its current position, so that the connection to the optimum cell is possible. Probability deterioration can be suppressed. Therefore, since the radio terminal 100 can derive any one of the radio base stations 200 as a connection base station, for example, it is not necessary to search for the radio base station 200 (cell search, Discovery) by a known method. That is, the radio terminal 100 does not need to sequentially scan for adoptable radio communication schemes (RAT) and search for the radio base station 200 located in the vicinity of the radio terminal 100. In this case, the radio terminal 100 does not need to perform cell search for the same number as the number of RATs present in the heterogeneous network. Therefore, the radio terminal 100 can reduce the processing load and the processing time for searching for the connection-destination radio base station 200.

Further, for example, as described above, as a conventional technique, the entire coverage area of the heterogeneous network is divided into area blocks of a certain size, the position of the wireless terminal 100 is associated with the area block number, and the communication history for each area block number is displayed. A method has been proposed that attempts to connect to an optimal cell. However, with this method, regardless of the size of the area block, the amount of prior work for dividing the entire coverage area of the heterogeneous network into area blocks is enormous, and the memory capacity of the wireless terminal also increases. On the other hand, in the present embodiment, when requesting a new communication connection, the wireless terminal 100 performs data communication based on the current position of the wireless terminal 100 and the position of the wireless terminal 100 included in the past communication history. It is possible to derive the radio base station 200 (connection base station) suitable for the above. For this reason, in this embodiment, in comparison with the proposed method described above, it is also necessary to perform a complicated work in advance to divide the entire coverage area of the heterogeneous network into area blocks (for example, area blocks considering three-dimensional position information). There is no increase in the capacity of the memory 160 of the wireless terminal 100.

Further, the wireless terminal 100 allocates a predetermined number (k) of communication histories having a small distance Di based on the current position information of the wireless terminal 100 and the position information of the wireless terminal 100 included in the past communication history. A connection base station is derived by giving priority to a radio base station having a large number of times. As a result, the wireless terminal 100 connects the wireless base station that has been used frequently in the communication history when the distance Di is small (in other words, the current position and the position at the time of past wireless communication are close). And can communicate stably with an appropriate connected base station having a communication record at the current position.

In addition, when the distance Di is equal to or less than the predetermined threshold value Dth, the wireless terminal 100 preferentially selects a wireless base station having a large number of allocations in the past predetermined number (k) of communication histories as a connection base station. To derive. This eliminates the communication history in which the distance Di is greater than the predetermined threshold value Dth (in other words, the communication history when the position of the wireless terminal 100 in the past wireless communication is far away from the current position) and performs higher-level communication. Since the history table T2 can be generated, the radio terminal 100 can assign more appropriate radio resources (for example, identification numbers of radio base stations) along the network environment provided around the current position. it can.

In addition, the wireless terminal 100 further accumulates information on the amount of data communication with the connecting base station as a communication history, and the data communication amount is the predetermined number (k) of past communication histories with a small distance Di. A connection base station is derived with priority given to many radio base stations. As a result, for example, a connection base that can provide a small cell (in other words, a cell with a high possibility of a large amount of communication data) capable of providing high-speed throughput such as 5G (fifth generation mobile communication system) to the heterogeneous network 20. It becomes possible to assign stations with priority, and it becomes easy to perform a comfortable amount of communication data.

Further, when data communication is performed with the derived connection base station, the wireless terminal 100 stores information on the connection base station regarding data communication as a communication history associated with the current position information of the wireless terminal 100. It accumulates in 160. As a result, the wireless terminal 100 stores, in the memory 160, a communication history in which the identification number of the connected base station that is the communication partner is associated with the position at the time of communication as a communication result of actually performing wireless communication. Can learn.

Further, the radio terminal 100 further accumulates information on the radio frequency used for data communication with the connected base station as a communication history, and uses the radio frequency information included in the communication history to communicate with the connected base station. The radio frequency used for data communication is derived. The radio terminal 100 performs data communication with the derived connection base station using the derived radio frequency. As a result, the radio terminal 100 can manage not only the identification number of the connecting base station but also the identification number of the radio frequency (carrier frequency) at the time of radio communication in association with the position information as a radio resource. Therefore, it is possible to derive an appropriate connection base station and radio frequency when there is a request, and to perform quick communication without waste.

In addition, the wireless terminal 100 derives the connection base station and the radio frequency by giving priority to the radio base station and the radio frequency with a large number of allocations in a predetermined number (k) of communication histories with a small distance Di. As a result, the wireless terminal 100 uses the radio frequency that has been used many times in the communication history when the distance Di is small (in other words, the current position is close to the position at the time of past wireless communication). It is possible to stably communicate with an appropriate connected base station having a communication record at the position of.

In addition, when the distance Di is equal to or less than the predetermined threshold value Dth, the wireless terminal 100 preferentially connects the wireless base station and the wireless frequency that are frequently assigned in the predetermined number (k) of past communication histories. Deriving base stations and radio frequencies. This eliminates the communication history in which the distance Di is greater than the predetermined threshold value Dth (in other words, the communication history when the position of the wireless terminal 100 in the past wireless communication is far away from the current position) and performs higher-level communication. Since the history table T2 can be generated, the radio terminal 100 can more appropriately use radio resources (for example, an identification number of a radio base station and an identification number of a radio frequency) along the network environment provided around the current position. Assignments can be made.

In addition, the radio terminal 100 further accumulates, as a communication history, information on the radio frequency used for data communication with the connected base station and information on the amount of data communication with the connected base station, and a predetermined number with a small distance Di. (K) Among the communication histories, a connection base station and a radio frequency are derived giving priority to a radio base station and a radio frequency with a large amount of data communication. As a result, for example, a connection base that can provide a small cell (in other words, a cell with a high possibility of a large amount of communication data) capable of providing high-speed throughput such as 5G (fifth generation mobile communication system) to the heterogeneous network 20. Stations and radio frequencies can be preferentially assigned, and a comfortable amount of communication data can be easily obtained.

Further, when data communication is performed with the derived connection base station, the radio terminal 100 associates information on the connection base station regarding data communication and information on the radio frequency with the current position information of the radio terminal 100. Is stored in the memory 160 as a communication history. As a result, the wireless terminal 100 has a communication history in which the identification number of the connected base station and the identification number of the wireless frequency as the communication partner are associated with the position at the time of communication as a communication record of actually performing the wireless communication. It can be stored in the memory 160 for learning.

Further, the position information of the wireless terminal 100 is, for example, a combination of information (latitude, longitude, altitude) that is effective outdoors, and the wireless terminal 100 sets the distance Di with priority given to, for example, altitude out of latitude, longitude, and altitude. To derive. Even if the latitude and longitude are the same in the position information of the wireless terminal 100, the communication environment may differ greatly if the altitude is different. Therefore, the radio terminal 100 can derive a connection base station and a radio frequency that can provide a communication environment suitable for the current position of the radio terminal 100 by calculating the distance Di with priority on altitude.

Further, in the present embodiment, when the wireless terminal 100 is located indoors or near the boundary between the outdoors and indoors, the position information of the wireless terminal 100 is relative to a plurality of BLE beacons 60 installed indoors. It may be position information obtained by a simple distance. As a result, when the wireless terminal 100 is located outdoors, the position can be specified by information (latitude, longitude, altitude) calculated by the GPS receiving unit 102, for example, and on the other hand, indoors or between outdoor and indoor When located near the boundary, for example, the position can be specified by information on the relative distance from the BLE beacon 60 calculated by the BLE receiver 122.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood. Moreover, you may combine each component in the above-mentioned embodiment arbitrarily in the range which does not deviate from the meaning of invention.

Note that this application is based on a Japanese patent application filed on December 6, 2016 (Japanese Patent Application No. 2016-236917), the contents of which are incorporated herein by reference.

The present disclosure relates to a wireless terminal and a wireless device that determine and assign a wireless base station to be a communication partner at the time of a wireless communication connection request based on the communication history at the current position of the wireless communication device, and suppress deterioration in the optimal connection probability to the cell. This is useful as a base station allocation method.

10 Wireless Communication System 20 Heterogeneous Network 21 Uplink (Uplink)
22 Downlink (Downlink)
50 GPS satellite 60 BLE beacon 100 Wireless terminal 101 GPS antenna 102 GPS receiver 103 Position information generator 104 Base station derivation unit 105 Radio resource allocation manager 106 Transmission packet generator 107 Radio transmitter 108 Transmit antenna 109 Receiver antenna 110 Radio reception Unit 111 received packet decoding unit 121 BLE antenna 122 BLE receiving unit 150 processor 160 memory 200 wireless base station T1 cumulative communication history table T2 upper communication history table

Claims

A wireless terminal capable of communicating with a plurality of wireless base stations via a network in which a plurality of wireless communication methods are used together,
An accumulator that accumulates at least location information of the radio terminal and information about the radio base station as a communication history at the time of past communication with each of the radio base stations;
An acquisition unit for acquiring position information of the wireless terminal;
A derivation unit for deriving a connection base station as a radio base station used for data communication from the plurality of radio base stations based on the acquired location information of the radio terminal and the communication history accumulated in the accumulation unit When,
A communication unit that performs the data communication with the derived connection base station,
Wireless terminal.
The derivation unit selects a radio base station having a large number of allocations in a predetermined number of communication histories having a small distance based on the acquired location information of the radio terminal and the location information of the radio terminal included in the communication history. Deriving the connected base station with priority,
The wireless terminal according to claim 1.
The derivation unit derives the connection base station in preference to a radio base station having a large number of allocations in the predetermined number of communication histories when the distance is equal to or less than a predetermined threshold.
The wireless terminal according to claim 2.
The accumulation unit further accumulates information on the amount of data communication with the connected base station as the communication history,
The deriving unit includes a radio base having a large amount of data communication in a predetermined number of communication histories having a small distance based on the acquired position information of the wireless terminal and the position information of the wireless terminal included in the communication history. Deriving the connected base station in preference to the station,
The wireless terminal according to claim 1.
When the data communication is performed with the derived connection base station, the storage unit includes information on the connection base station regarding the data communication as a communication history associated with the acquired location information of the wireless terminal. An update unit for storing
The wireless terminal according to claim 1.
The accumulation unit further accumulates radio frequency information used for data communication with the connection base station as the communication history,
The derivation unit derives a radio frequency used for data communication with the connection base station using the information on the radio frequency included in the communication history,
The communication unit performs the data communication with the derived connection base station using the derived radio frequency.
The wireless terminal according to claim 1.
The deriving unit includes a radio base station having a large number of allocations in a predetermined number of communication histories having a small distance based on the acquired position information of the wireless terminal and the position information of the wireless terminal included in the communication history, and Deriving the connection base station and the radio frequency in preference to a radio frequency;
The wireless terminal according to claim 6.
When the distance is equal to or less than a predetermined threshold, the deriving unit gives priority to the connection base station and the radio frequency in the predetermined number of communication histories, giving priority to a radio base station and a radio frequency with a large number of allocations. To derive,
The wireless terminal according to claim 7.
The storage unit further stores, as the communication history, radio frequency information used for data communication with the connection base station and data communication volume information with the connection base station,
The deriving unit includes a radio base having a large amount of data communication in a predetermined number of communication histories having a small distance based on the acquired position information of the wireless terminal and the position information of the wireless terminal included in the communication history. Deriving the connected base station and the radio frequency in preference to the station and the radio frequency
The wireless terminal according to claim 1.
When the data communication is performed with the derived connection base station, the information regarding the connection base station regarding the data communication and the information on the radio frequency are associated with the acquired position information of the wireless terminal. An update unit that stores the communication history in the storage unit;
The wireless terminal according to claim 6.
The location information of the wireless terminal has latitude, longitude and altitude,
The derivation unit derives the distance by giving priority to the altitude among the latitude, longitude, and altitude.
The wireless terminal according to claim 2 or 7.
A wireless base station allocation method in a wireless terminal capable of communicating with a plurality of wireless base stations via a network in which a plurality of wireless communication methods are used in combination,
Storing at least the position information of the wireless terminal and information about the wireless base station in a storage unit as a communication history during past communication with each of the wireless base stations;
Obtaining location information of the wireless terminal;
Deriving a connection base station as a radio base station used for data communication from the plurality of radio base stations based on the acquired location information of the radio terminal and the communication history accumulated in the accumulation unit; ,
Performing the data communication with the derived connection base station.
Radio base station allocation method.